CVE-2026-50248
BOGUS configured primary hostname accepted for XFR in auth/rpz zones
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, when an auth/rpz zone has a configured primary hostname that resolves to BOGUS A/AAAA, it is still considered as a possible XFR endpoint. A malicious actor that can spoof the hostname's A/AAAA record (no valid RRSIG required) becomes the zone's XFR primary and can replaces the entire zone/the resolver's entire response policy.
| CWE | CWE-345 |
| Vendor | nlnet labs |
| Product | unbound |
| Published | Jul 22, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Affected Versions
NLnet Labs / Unbound
1.7.0 < 1.25.2
References
Credits
Qifan Zhang (Palo Alto Networks)